1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * device.h - generic, centralized driver model 4 * 5 * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org> 6 * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de> 7 * Copyright (c) 2008-2009 Novell Inc. 8 * 9 * See Documentation/driver-api/driver-model/ for more information. 10 */ 11 12 #ifndef _DEVICE_H_ 13 #define _DEVICE_H_ 14 15 #include <linux/dev_printk.h> 16 #include <linux/energy_model.h> 17 #include <linux/ioport.h> 18 #include <linux/kobject.h> 19 #include <linux/klist.h> 20 #include <linux/list.h> 21 #include <linux/lockdep.h> 22 #include <linux/compiler.h> 23 #include <linux/types.h> 24 #include <linux/mutex.h> 25 #include <linux/pm.h> 26 #include <linux/atomic.h> 27 #include <linux/uidgid.h> 28 #include <linux/gfp.h> 29 #include <linux/overflow.h> 30 #include <linux/device/bus.h> 31 #include <linux/device/class.h> 32 #include <linux/device/driver.h> 33 #include <linux/cleanup.h> 34 #include <asm/device.h> 35 36 struct device; 37 struct device_private; 38 struct device_driver; 39 struct driver_private; 40 struct module; 41 struct class; 42 struct subsys_private; 43 struct device_node; 44 struct fwnode_handle; 45 struct iommu_group; 46 struct dev_pin_info; 47 struct dev_iommu; 48 struct msi_device_data; 49 50 /** 51 * struct subsys_interface - interfaces to device functions 52 * @name: name of the device function 53 * @subsys: subsystem of the devices to attach to 54 * @node: the list of functions registered at the subsystem 55 * @add_dev: device hookup to device function handler 56 * @remove_dev: device hookup to device function handler 57 * 58 * Simple interfaces attached to a subsystem. Multiple interfaces can 59 * attach to a subsystem and its devices. Unlike drivers, they do not 60 * exclusively claim or control devices. Interfaces usually represent 61 * a specific functionality of a subsystem/class of devices. 62 */ 63 struct subsys_interface { 64 const char *name; 65 const struct bus_type *subsys; 66 struct list_head node; 67 int (*add_dev)(struct device *dev, struct subsys_interface *sif); 68 void (*remove_dev)(struct device *dev, struct subsys_interface *sif); 69 }; 70 71 int subsys_interface_register(struct subsys_interface *sif); 72 void subsys_interface_unregister(struct subsys_interface *sif); 73 74 int subsys_system_register(const struct bus_type *subsys, 75 const struct attribute_group **groups); 76 int subsys_virtual_register(const struct bus_type *subsys, 77 const struct attribute_group **groups); 78 79 /* 80 * The type of device, "struct device" is embedded in. A class 81 * or bus can contain devices of different types 82 * like "partitions" and "disks", "mouse" and "event". 83 * This identifies the device type and carries type-specific 84 * information, equivalent to the kobj_type of a kobject. 85 * If "name" is specified, the uevent will contain it in 86 * the DEVTYPE variable. 87 */ 88 struct device_type { 89 const char *name; 90 const struct attribute_group **groups; 91 int (*uevent)(const struct device *dev, struct kobj_uevent_env *env); 92 char *(*devnode)(const struct device *dev, umode_t *mode, 93 kuid_t *uid, kgid_t *gid); 94 void (*release)(struct device *dev); 95 96 const struct dev_pm_ops *pm; 97 }; 98 99 /** 100 * struct device_attribute - Interface for exporting device attributes. 101 * @attr: sysfs attribute definition. 102 * @show: Show handler. 103 * @store: Store handler. 104 */ 105 struct device_attribute { 106 struct attribute attr; 107 ssize_t (*show)(struct device *dev, struct device_attribute *attr, 108 char *buf); 109 ssize_t (*store)(struct device *dev, struct device_attribute *attr, 110 const char *buf, size_t count); 111 }; 112 113 /** 114 * struct dev_ext_attribute - Exported device attribute with extra context. 115 * @attr: Exported device attribute. 116 * @var: Pointer to context. 117 */ 118 struct dev_ext_attribute { 119 struct device_attribute attr; 120 void *var; 121 }; 122 123 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr, 124 char *buf); 125 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr, 126 const char *buf, size_t count); 127 ssize_t device_show_int(struct device *dev, struct device_attribute *attr, 128 char *buf); 129 ssize_t device_store_int(struct device *dev, struct device_attribute *attr, 130 const char *buf, size_t count); 131 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr, 132 char *buf); 133 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr, 134 const char *buf, size_t count); 135 136 /** 137 * DEVICE_ATTR - Define a device attribute. 138 * @_name: Attribute name. 139 * @_mode: File mode. 140 * @_show: Show handler. Optional, but mandatory if attribute is readable. 141 * @_store: Store handler. Optional, but mandatory if attribute is writable. 142 * 143 * Convenience macro for defining a struct device_attribute. 144 * 145 * For example, ``DEVICE_ATTR(foo, 0644, foo_show, foo_store);`` expands to: 146 * 147 * .. code-block:: c 148 * 149 * struct device_attribute dev_attr_foo = { 150 * .attr = { .name = "foo", .mode = 0644 }, 151 * .show = foo_show, 152 * .store = foo_store, 153 * }; 154 */ 155 #define DEVICE_ATTR(_name, _mode, _show, _store) \ 156 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store) 157 158 /** 159 * DEVICE_ATTR_PREALLOC - Define a preallocated device attribute. 160 * @_name: Attribute name. 161 * @_mode: File mode. 162 * @_show: Show handler. Optional, but mandatory if attribute is readable. 163 * @_store: Store handler. Optional, but mandatory if attribute is writable. 164 * 165 * Like DEVICE_ATTR(), but ``SYSFS_PREALLOC`` is set on @_mode. 166 */ 167 #define DEVICE_ATTR_PREALLOC(_name, _mode, _show, _store) \ 168 struct device_attribute dev_attr_##_name = \ 169 __ATTR_PREALLOC(_name, _mode, _show, _store) 170 171 /** 172 * DEVICE_ATTR_RW - Define a read-write device attribute. 173 * @_name: Attribute name. 174 * 175 * Like DEVICE_ATTR(), but @_mode is 0644, @_show is <_name>_show, 176 * and @_store is <_name>_store. 177 */ 178 #define DEVICE_ATTR_RW(_name) \ 179 struct device_attribute dev_attr_##_name = __ATTR_RW(_name) 180 181 /** 182 * DEVICE_ATTR_ADMIN_RW - Define an admin-only read-write device attribute. 183 * @_name: Attribute name. 184 * 185 * Like DEVICE_ATTR_RW(), but @_mode is 0600. 186 */ 187 #define DEVICE_ATTR_ADMIN_RW(_name) \ 188 struct device_attribute dev_attr_##_name = __ATTR_RW_MODE(_name, 0600) 189 190 /** 191 * DEVICE_ATTR_RO - Define a readable device attribute. 192 * @_name: Attribute name. 193 * 194 * Like DEVICE_ATTR(), but @_mode is 0444 and @_show is <_name>_show. 195 */ 196 #define DEVICE_ATTR_RO(_name) \ 197 struct device_attribute dev_attr_##_name = __ATTR_RO(_name) 198 199 /** 200 * DEVICE_ATTR_ADMIN_RO - Define an admin-only readable device attribute. 201 * @_name: Attribute name. 202 * 203 * Like DEVICE_ATTR_RO(), but @_mode is 0400. 204 */ 205 #define DEVICE_ATTR_ADMIN_RO(_name) \ 206 struct device_attribute dev_attr_##_name = __ATTR_RO_MODE(_name, 0400) 207 208 /** 209 * DEVICE_ATTR_WO - Define an admin-only writable device attribute. 210 * @_name: Attribute name. 211 * 212 * Like DEVICE_ATTR(), but @_mode is 0200 and @_store is <_name>_store. 213 */ 214 #define DEVICE_ATTR_WO(_name) \ 215 struct device_attribute dev_attr_##_name = __ATTR_WO(_name) 216 217 /** 218 * DEVICE_ULONG_ATTR - Define a device attribute backed by an unsigned long. 219 * @_name: Attribute name. 220 * @_mode: File mode. 221 * @_var: Identifier of unsigned long. 222 * 223 * Like DEVICE_ATTR(), but @_show and @_store are automatically provided 224 * such that reads and writes to the attribute from userspace affect @_var. 225 */ 226 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \ 227 struct dev_ext_attribute dev_attr_##_name = \ 228 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) } 229 230 /** 231 * DEVICE_INT_ATTR - Define a device attribute backed by an int. 232 * @_name: Attribute name. 233 * @_mode: File mode. 234 * @_var: Identifier of int. 235 * 236 * Like DEVICE_ULONG_ATTR(), but @_var is an int. 237 */ 238 #define DEVICE_INT_ATTR(_name, _mode, _var) \ 239 struct dev_ext_attribute dev_attr_##_name = \ 240 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) } 241 242 /** 243 * DEVICE_BOOL_ATTR - Define a device attribute backed by a bool. 244 * @_name: Attribute name. 245 * @_mode: File mode. 246 * @_var: Identifier of bool. 247 * 248 * Like DEVICE_ULONG_ATTR(), but @_var is a bool. 249 */ 250 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \ 251 struct dev_ext_attribute dev_attr_##_name = \ 252 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) } 253 254 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \ 255 struct device_attribute dev_attr_##_name = \ 256 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) 257 258 int device_create_file(struct device *device, 259 const struct device_attribute *entry); 260 void device_remove_file(struct device *dev, 261 const struct device_attribute *attr); 262 bool device_remove_file_self(struct device *dev, 263 const struct device_attribute *attr); 264 int __must_check device_create_bin_file(struct device *dev, 265 const struct bin_attribute *attr); 266 void device_remove_bin_file(struct device *dev, 267 const struct bin_attribute *attr); 268 269 /* device resource management */ 270 typedef void (*dr_release_t)(struct device *dev, void *res); 271 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data); 272 273 void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp, 274 int nid, const char *name) __malloc; 275 #define devres_alloc(release, size, gfp) \ 276 __devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release) 277 #define devres_alloc_node(release, size, gfp, nid) \ 278 __devres_alloc_node(release, size, gfp, nid, #release) 279 280 void devres_for_each_res(struct device *dev, dr_release_t release, 281 dr_match_t match, void *match_data, 282 void (*fn)(struct device *, void *, void *), 283 void *data); 284 void devres_free(void *res); 285 void devres_add(struct device *dev, void *res); 286 void *devres_find(struct device *dev, dr_release_t release, 287 dr_match_t match, void *match_data); 288 void *devres_get(struct device *dev, void *new_res, 289 dr_match_t match, void *match_data); 290 void *devres_remove(struct device *dev, dr_release_t release, 291 dr_match_t match, void *match_data); 292 int devres_destroy(struct device *dev, dr_release_t release, 293 dr_match_t match, void *match_data); 294 int devres_release(struct device *dev, dr_release_t release, 295 dr_match_t match, void *match_data); 296 297 /* devres group */ 298 void * __must_check devres_open_group(struct device *dev, void *id, gfp_t gfp); 299 void devres_close_group(struct device *dev, void *id); 300 void devres_remove_group(struct device *dev, void *id); 301 int devres_release_group(struct device *dev, void *id); 302 303 /* managed devm_k.alloc/kfree for device drivers */ 304 void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __alloc_size(2); 305 void *devm_krealloc(struct device *dev, void *ptr, size_t size, 306 gfp_t gfp) __must_check __realloc_size(3); 307 __printf(3, 0) char *devm_kvasprintf(struct device *dev, gfp_t gfp, 308 const char *fmt, va_list ap) __malloc; 309 __printf(3, 4) char *devm_kasprintf(struct device *dev, gfp_t gfp, 310 const char *fmt, ...) __malloc; 311 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp) 312 { 313 return devm_kmalloc(dev, size, gfp | __GFP_ZERO); 314 } 315 static inline void *devm_kmalloc_array(struct device *dev, 316 size_t n, size_t size, gfp_t flags) 317 { 318 size_t bytes; 319 320 if (unlikely(check_mul_overflow(n, size, &bytes))) 321 return NULL; 322 323 return devm_kmalloc(dev, bytes, flags); 324 } 325 static inline void *devm_kcalloc(struct device *dev, 326 size_t n, size_t size, gfp_t flags) 327 { 328 return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO); 329 } 330 static inline __realloc_size(3, 4) void * __must_check 331 devm_krealloc_array(struct device *dev, void *p, size_t new_n, size_t new_size, gfp_t flags) 332 { 333 size_t bytes; 334 335 if (unlikely(check_mul_overflow(new_n, new_size, &bytes))) 336 return NULL; 337 338 return devm_krealloc(dev, p, bytes, flags); 339 } 340 341 void devm_kfree(struct device *dev, const void *p); 342 char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc; 343 const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp); 344 void *devm_kmemdup(struct device *dev, const void *src, size_t len, gfp_t gfp) 345 __realloc_size(3); 346 347 unsigned long devm_get_free_pages(struct device *dev, 348 gfp_t gfp_mask, unsigned int order); 349 void devm_free_pages(struct device *dev, unsigned long addr); 350 351 #ifdef CONFIG_HAS_IOMEM 352 void __iomem *devm_ioremap_resource(struct device *dev, 353 const struct resource *res); 354 void __iomem *devm_ioremap_resource_wc(struct device *dev, 355 const struct resource *res); 356 357 void __iomem *devm_of_iomap(struct device *dev, 358 struct device_node *node, int index, 359 resource_size_t *size); 360 #else 361 362 static inline 363 void __iomem *devm_ioremap_resource(struct device *dev, 364 const struct resource *res) 365 { 366 return ERR_PTR(-EINVAL); 367 } 368 369 static inline 370 void __iomem *devm_ioremap_resource_wc(struct device *dev, 371 const struct resource *res) 372 { 373 return ERR_PTR(-EINVAL); 374 } 375 376 static inline 377 void __iomem *devm_of_iomap(struct device *dev, 378 struct device_node *node, int index, 379 resource_size_t *size) 380 { 381 return ERR_PTR(-EINVAL); 382 } 383 384 #endif 385 386 /* allows to add/remove a custom action to devres stack */ 387 void devm_remove_action(struct device *dev, void (*action)(void *), void *data); 388 void devm_release_action(struct device *dev, void (*action)(void *), void *data); 389 390 int __devm_add_action(struct device *dev, void (*action)(void *), void *data, const char *name); 391 #define devm_add_action(dev, action, data) \ 392 __devm_add_action(dev, action, data, #action) 393 394 static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(void *), 395 void *data, const char *name) 396 { 397 int ret; 398 399 ret = __devm_add_action(dev, action, data, name); 400 if (ret) 401 action(data); 402 403 return ret; 404 } 405 #define devm_add_action_or_reset(dev, action, data) \ 406 __devm_add_action_or_reset(dev, action, data, #action) 407 408 /** 409 * devm_alloc_percpu - Resource-managed alloc_percpu 410 * @dev: Device to allocate per-cpu memory for 411 * @type: Type to allocate per-cpu memory for 412 * 413 * Managed alloc_percpu. Per-cpu memory allocated with this function is 414 * automatically freed on driver detach. 415 * 416 * RETURNS: 417 * Pointer to allocated memory on success, NULL on failure. 418 */ 419 #define devm_alloc_percpu(dev, type) \ 420 ((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \ 421 __alignof__(type))) 422 423 void __percpu *__devm_alloc_percpu(struct device *dev, size_t size, 424 size_t align); 425 void devm_free_percpu(struct device *dev, void __percpu *pdata); 426 427 struct device_dma_parameters { 428 /* 429 * a low level driver may set these to teach IOMMU code about 430 * sg limitations. 431 */ 432 unsigned int max_segment_size; 433 unsigned int min_align_mask; 434 unsigned long segment_boundary_mask; 435 }; 436 437 /** 438 * enum device_link_state - Device link states. 439 * @DL_STATE_NONE: The presence of the drivers is not being tracked. 440 * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present. 441 * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not. 442 * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present). 443 * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present. 444 * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding. 445 */ 446 enum device_link_state { 447 DL_STATE_NONE = -1, 448 DL_STATE_DORMANT = 0, 449 DL_STATE_AVAILABLE, 450 DL_STATE_CONSUMER_PROBE, 451 DL_STATE_ACTIVE, 452 DL_STATE_SUPPLIER_UNBIND, 453 }; 454 455 /* 456 * Device link flags. 457 * 458 * STATELESS: The core will not remove this link automatically. 459 * AUTOREMOVE_CONSUMER: Remove the link automatically on consumer driver unbind. 460 * PM_RUNTIME: If set, the runtime PM framework will use this link. 461 * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation. 462 * AUTOREMOVE_SUPPLIER: Remove the link automatically on supplier driver unbind. 463 * AUTOPROBE_CONSUMER: Probe consumer driver automatically after supplier binds. 464 * MANAGED: The core tracks presence of supplier/consumer drivers (internal). 465 * SYNC_STATE_ONLY: Link only affects sync_state() behavior. 466 * INFERRED: Inferred from data (eg: firmware) and not from driver actions. 467 */ 468 #define DL_FLAG_STATELESS BIT(0) 469 #define DL_FLAG_AUTOREMOVE_CONSUMER BIT(1) 470 #define DL_FLAG_PM_RUNTIME BIT(2) 471 #define DL_FLAG_RPM_ACTIVE BIT(3) 472 #define DL_FLAG_AUTOREMOVE_SUPPLIER BIT(4) 473 #define DL_FLAG_AUTOPROBE_CONSUMER BIT(5) 474 #define DL_FLAG_MANAGED BIT(6) 475 #define DL_FLAG_SYNC_STATE_ONLY BIT(7) 476 #define DL_FLAG_INFERRED BIT(8) 477 #define DL_FLAG_CYCLE BIT(9) 478 479 /** 480 * enum dl_dev_state - Device driver presence tracking information. 481 * @DL_DEV_NO_DRIVER: There is no driver attached to the device. 482 * @DL_DEV_PROBING: A driver is probing. 483 * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device. 484 * @DL_DEV_UNBINDING: The driver is unbinding from the device. 485 */ 486 enum dl_dev_state { 487 DL_DEV_NO_DRIVER = 0, 488 DL_DEV_PROBING, 489 DL_DEV_DRIVER_BOUND, 490 DL_DEV_UNBINDING, 491 }; 492 493 /** 494 * enum device_removable - Whether the device is removable. The criteria for a 495 * device to be classified as removable is determined by its subsystem or bus. 496 * @DEVICE_REMOVABLE_NOT_SUPPORTED: This attribute is not supported for this 497 * device (default). 498 * @DEVICE_REMOVABLE_UNKNOWN: Device location is Unknown. 499 * @DEVICE_FIXED: Device is not removable by the user. 500 * @DEVICE_REMOVABLE: Device is removable by the user. 501 */ 502 enum device_removable { 503 DEVICE_REMOVABLE_NOT_SUPPORTED = 0, /* must be 0 */ 504 DEVICE_REMOVABLE_UNKNOWN, 505 DEVICE_FIXED, 506 DEVICE_REMOVABLE, 507 }; 508 509 /** 510 * struct dev_links_info - Device data related to device links. 511 * @suppliers: List of links to supplier devices. 512 * @consumers: List of links to consumer devices. 513 * @defer_sync: Hook to global list of devices that have deferred sync_state. 514 * @status: Driver status information. 515 */ 516 struct dev_links_info { 517 struct list_head suppliers; 518 struct list_head consumers; 519 struct list_head defer_sync; 520 enum dl_dev_state status; 521 }; 522 523 /** 524 * struct dev_msi_info - Device data related to MSI 525 * @domain: The MSI interrupt domain associated to the device 526 * @data: Pointer to MSI device data 527 */ 528 struct dev_msi_info { 529 #ifdef CONFIG_GENERIC_MSI_IRQ 530 struct irq_domain *domain; 531 struct msi_device_data *data; 532 #endif 533 }; 534 535 /** 536 * enum device_physical_location_panel - Describes which panel surface of the 537 * system's housing the device connection point resides on. 538 * @DEVICE_PANEL_TOP: Device connection point is on the top panel. 539 * @DEVICE_PANEL_BOTTOM: Device connection point is on the bottom panel. 540 * @DEVICE_PANEL_LEFT: Device connection point is on the left panel. 541 * @DEVICE_PANEL_RIGHT: Device connection point is on the right panel. 542 * @DEVICE_PANEL_FRONT: Device connection point is on the front panel. 543 * @DEVICE_PANEL_BACK: Device connection point is on the back panel. 544 * @DEVICE_PANEL_UNKNOWN: The panel with device connection point is unknown. 545 */ 546 enum device_physical_location_panel { 547 DEVICE_PANEL_TOP, 548 DEVICE_PANEL_BOTTOM, 549 DEVICE_PANEL_LEFT, 550 DEVICE_PANEL_RIGHT, 551 DEVICE_PANEL_FRONT, 552 DEVICE_PANEL_BACK, 553 DEVICE_PANEL_UNKNOWN, 554 }; 555 556 /** 557 * enum device_physical_location_vertical_position - Describes vertical 558 * position of the device connection point on the panel surface. 559 * @DEVICE_VERT_POS_UPPER: Device connection point is at upper part of panel. 560 * @DEVICE_VERT_POS_CENTER: Device connection point is at center part of panel. 561 * @DEVICE_VERT_POS_LOWER: Device connection point is at lower part of panel. 562 */ 563 enum device_physical_location_vertical_position { 564 DEVICE_VERT_POS_UPPER, 565 DEVICE_VERT_POS_CENTER, 566 DEVICE_VERT_POS_LOWER, 567 }; 568 569 /** 570 * enum device_physical_location_horizontal_position - Describes horizontal 571 * position of the device connection point on the panel surface. 572 * @DEVICE_HORI_POS_LEFT: Device connection point is at left part of panel. 573 * @DEVICE_HORI_POS_CENTER: Device connection point is at center part of panel. 574 * @DEVICE_HORI_POS_RIGHT: Device connection point is at right part of panel. 575 */ 576 enum device_physical_location_horizontal_position { 577 DEVICE_HORI_POS_LEFT, 578 DEVICE_HORI_POS_CENTER, 579 DEVICE_HORI_POS_RIGHT, 580 }; 581 582 /** 583 * struct device_physical_location - Device data related to physical location 584 * of the device connection point. 585 * @panel: Panel surface of the system's housing that the device connection 586 * point resides on. 587 * @vertical_position: Vertical position of the device connection point within 588 * the panel. 589 * @horizontal_position: Horizontal position of the device connection point 590 * within the panel. 591 * @dock: Set if the device connection point resides in a docking station or 592 * port replicator. 593 * @lid: Set if this device connection point resides on the lid of laptop 594 * system. 595 */ 596 struct device_physical_location { 597 enum device_physical_location_panel panel; 598 enum device_physical_location_vertical_position vertical_position; 599 enum device_physical_location_horizontal_position horizontal_position; 600 bool dock; 601 bool lid; 602 }; 603 604 /** 605 * struct device - The basic device structure 606 * @parent: The device's "parent" device, the device to which it is attached. 607 * In most cases, a parent device is some sort of bus or host 608 * controller. If parent is NULL, the device, is a top-level device, 609 * which is not usually what you want. 610 * @p: Holds the private data of the driver core portions of the device. 611 * See the comment of the struct device_private for detail. 612 * @kobj: A top-level, abstract class from which other classes are derived. 613 * @init_name: Initial name of the device. 614 * @type: The type of device. 615 * This identifies the device type and carries type-specific 616 * information. 617 * @mutex: Mutex to synchronize calls to its driver. 618 * @bus: Type of bus device is on. 619 * @driver: Which driver has allocated this 620 * @platform_data: Platform data specific to the device. 621 * Example: For devices on custom boards, as typical of embedded 622 * and SOC based hardware, Linux often uses platform_data to point 623 * to board-specific structures describing devices and how they 624 * are wired. That can include what ports are available, chip 625 * variants, which GPIO pins act in what additional roles, and so 626 * on. This shrinks the "Board Support Packages" (BSPs) and 627 * minimizes board-specific #ifdefs in drivers. 628 * @driver_data: Private pointer for driver specific info. 629 * @links: Links to suppliers and consumers of this device. 630 * @power: For device power management. 631 * See Documentation/driver-api/pm/devices.rst for details. 632 * @pm_domain: Provide callbacks that are executed during system suspend, 633 * hibernation, system resume and during runtime PM transitions 634 * along with subsystem-level and driver-level callbacks. 635 * @em_pd: device's energy model performance domain 636 * @pins: For device pin management. 637 * See Documentation/driver-api/pin-control.rst for details. 638 * @msi: MSI related data 639 * @numa_node: NUMA node this device is close to. 640 * @dma_ops: DMA mapping operations for this device. 641 * @dma_mask: Dma mask (if dma'ble device). 642 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all 643 * hardware supports 64-bit addresses for consistent allocations 644 * such descriptors. 645 * @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller 646 * DMA limit than the device itself supports. 647 * @dma_range_map: map for DMA memory ranges relative to that of RAM 648 * @dma_parms: A low level driver may set these to teach IOMMU code about 649 * segment limitations. 650 * @dma_pools: Dma pools (if dma'ble device). 651 * @dma_mem: Internal for coherent mem override. 652 * @cma_area: Contiguous memory area for dma allocations 653 * @dma_io_tlb_mem: Software IO TLB allocator. Not for driver use. 654 * @dma_io_tlb_pools: List of transient swiotlb memory pools. 655 * @dma_io_tlb_lock: Protects changes to the list of active pools. 656 * @dma_uses_io_tlb: %true if device has used the software IO TLB. 657 * @archdata: For arch-specific additions. 658 * @of_node: Associated device tree node. 659 * @fwnode: Associated device node supplied by platform firmware. 660 * @devt: For creating the sysfs "dev". 661 * @id: device instance 662 * @devres_lock: Spinlock to protect the resource of the device. 663 * @devres_head: The resources list of the device. 664 * @class: The class of the device. 665 * @groups: Optional attribute groups. 666 * @release: Callback to free the device after all references have 667 * gone away. This should be set by the allocator of the 668 * device (i.e. the bus driver that discovered the device). 669 * @iommu_group: IOMMU group the device belongs to. 670 * @iommu: Per device generic IOMMU runtime data 671 * @physical_location: Describes physical location of the device connection 672 * point in the system housing. 673 * @removable: Whether the device can be removed from the system. This 674 * should be set by the subsystem / bus driver that discovered 675 * the device. 676 * 677 * @offline_disabled: If set, the device is permanently online. 678 * @offline: Set after successful invocation of bus type's .offline(). 679 * @of_node_reused: Set if the device-tree node is shared with an ancestor 680 * device. 681 * @state_synced: The hardware state of this device has been synced to match 682 * the software state of this device by calling the driver/bus 683 * sync_state() callback. 684 * @can_match: The device has matched with a driver at least once or it is in 685 * a bus (like AMBA) which can't check for matching drivers until 686 * other devices probe successfully. 687 * @dma_coherent: this particular device is dma coherent, even if the 688 * architecture supports non-coherent devices. 689 * @dma_ops_bypass: If set to %true then the dma_ops are bypassed for the 690 * streaming DMA operations (->map_* / ->unmap_* / ->sync_*), 691 * and optionall (if the coherent mask is large enough) also 692 * for dma allocations. This flag is managed by the dma ops 693 * instance from ->dma_supported. 694 * 695 * At the lowest level, every device in a Linux system is represented by an 696 * instance of struct device. The device structure contains the information 697 * that the device model core needs to model the system. Most subsystems, 698 * however, track additional information about the devices they host. As a 699 * result, it is rare for devices to be represented by bare device structures; 700 * instead, that structure, like kobject structures, is usually embedded within 701 * a higher-level representation of the device. 702 */ 703 struct device { 704 struct kobject kobj; 705 struct device *parent; 706 707 struct device_private *p; 708 709 const char *init_name; /* initial name of the device */ 710 const struct device_type *type; 711 712 const struct bus_type *bus; /* type of bus device is on */ 713 struct device_driver *driver; /* which driver has allocated this 714 device */ 715 void *platform_data; /* Platform specific data, device 716 core doesn't touch it */ 717 void *driver_data; /* Driver data, set and get with 718 dev_set_drvdata/dev_get_drvdata */ 719 struct mutex mutex; /* mutex to synchronize calls to 720 * its driver. 721 */ 722 723 struct dev_links_info links; 724 struct dev_pm_info power; 725 struct dev_pm_domain *pm_domain; 726 727 #ifdef CONFIG_ENERGY_MODEL 728 struct em_perf_domain *em_pd; 729 #endif 730 731 #ifdef CONFIG_PINCTRL 732 struct dev_pin_info *pins; 733 #endif 734 struct dev_msi_info msi; 735 #ifdef CONFIG_DMA_OPS 736 const struct dma_map_ops *dma_ops; 737 #endif 738 u64 *dma_mask; /* dma mask (if dma'able device) */ 739 u64 coherent_dma_mask;/* Like dma_mask, but for 740 alloc_coherent mappings as 741 not all hardware supports 742 64 bit addresses for consistent 743 allocations such descriptors. */ 744 u64 bus_dma_limit; /* upstream dma constraint */ 745 const struct bus_dma_region *dma_range_map; 746 747 struct device_dma_parameters *dma_parms; 748 749 struct list_head dma_pools; /* dma pools (if dma'ble) */ 750 751 #ifdef CONFIG_DMA_DECLARE_COHERENT 752 struct dma_coherent_mem *dma_mem; /* internal for coherent mem 753 override */ 754 #endif 755 #ifdef CONFIG_DMA_CMA 756 struct cma *cma_area; /* contiguous memory area for dma 757 allocations */ 758 #endif 759 #ifdef CONFIG_SWIOTLB 760 struct io_tlb_mem *dma_io_tlb_mem; 761 #endif 762 #ifdef CONFIG_SWIOTLB_DYNAMIC 763 struct list_head dma_io_tlb_pools; 764 spinlock_t dma_io_tlb_lock; 765 bool dma_uses_io_tlb; 766 #endif 767 /* arch specific additions */ 768 struct dev_archdata archdata; 769 770 struct device_node *of_node; /* associated device tree node */ 771 struct fwnode_handle *fwnode; /* firmware device node */ 772 773 #ifdef CONFIG_NUMA 774 int numa_node; /* NUMA node this device is close to */ 775 #endif 776 dev_t devt; /* dev_t, creates the sysfs "dev" */ 777 u32 id; /* device instance */ 778 779 spinlock_t devres_lock; 780 struct list_head devres_head; 781 782 const struct class *class; 783 const struct attribute_group **groups; /* optional groups */ 784 785 void (*release)(struct device *dev); 786 struct iommu_group *iommu_group; 787 struct dev_iommu *iommu; 788 789 struct device_physical_location *physical_location; 790 791 enum device_removable removable; 792 793 bool offline_disabled:1; 794 bool offline:1; 795 bool of_node_reused:1; 796 bool state_synced:1; 797 bool can_match:1; 798 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ 799 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ 800 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) 801 bool dma_coherent:1; 802 #endif 803 #ifdef CONFIG_DMA_OPS_BYPASS 804 bool dma_ops_bypass : 1; 805 #endif 806 }; 807 808 /** 809 * struct device_link - Device link representation. 810 * @supplier: The device on the supplier end of the link. 811 * @s_node: Hook to the supplier device's list of links to consumers. 812 * @consumer: The device on the consumer end of the link. 813 * @c_node: Hook to the consumer device's list of links to suppliers. 814 * @link_dev: device used to expose link details in sysfs 815 * @status: The state of the link (with respect to the presence of drivers). 816 * @flags: Link flags. 817 * @rpm_active: Whether or not the consumer device is runtime-PM-active. 818 * @kref: Count repeated addition of the same link. 819 * @rm_work: Work structure used for removing the link. 820 * @supplier_preactivated: Supplier has been made active before consumer probe. 821 */ 822 struct device_link { 823 struct device *supplier; 824 struct list_head s_node; 825 struct device *consumer; 826 struct list_head c_node; 827 struct device link_dev; 828 enum device_link_state status; 829 u32 flags; 830 refcount_t rpm_active; 831 struct kref kref; 832 struct work_struct rm_work; 833 bool supplier_preactivated; /* Owned by consumer probe. */ 834 }; 835 836 #define kobj_to_dev(__kobj) container_of_const(__kobj, struct device, kobj) 837 838 /** 839 * device_iommu_mapped - Returns true when the device DMA is translated 840 * by an IOMMU 841 * @dev: Device to perform the check on 842 */ 843 static inline bool device_iommu_mapped(struct device *dev) 844 { 845 return (dev->iommu_group != NULL); 846 } 847 848 /* Get the wakeup routines, which depend on struct device */ 849 #include <linux/pm_wakeup.h> 850 851 /** 852 * dev_name - Return a device's name. 853 * @dev: Device with name to get. 854 * Return: The kobject name of the device, or its initial name if unavailable. 855 */ 856 static inline const char *dev_name(const struct device *dev) 857 { 858 /* Use the init name until the kobject becomes available */ 859 if (dev->init_name) 860 return dev->init_name; 861 862 return kobject_name(&dev->kobj); 863 } 864 865 /** 866 * dev_bus_name - Return a device's bus/class name, if at all possible 867 * @dev: struct device to get the bus/class name of 868 * 869 * Will return the name of the bus/class the device is attached to. If it is 870 * not attached to a bus/class, an empty string will be returned. 871 */ 872 static inline const char *dev_bus_name(const struct device *dev) 873 { 874 return dev->bus ? dev->bus->name : (dev->class ? dev->class->name : ""); 875 } 876 877 __printf(2, 3) int dev_set_name(struct device *dev, const char *name, ...); 878 879 #ifdef CONFIG_NUMA 880 static inline int dev_to_node(struct device *dev) 881 { 882 return dev->numa_node; 883 } 884 static inline void set_dev_node(struct device *dev, int node) 885 { 886 dev->numa_node = node; 887 } 888 #else 889 static inline int dev_to_node(struct device *dev) 890 { 891 return NUMA_NO_NODE; 892 } 893 static inline void set_dev_node(struct device *dev, int node) 894 { 895 } 896 #endif 897 898 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev) 899 { 900 #ifdef CONFIG_GENERIC_MSI_IRQ 901 return dev->msi.domain; 902 #else 903 return NULL; 904 #endif 905 } 906 907 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d) 908 { 909 #ifdef CONFIG_GENERIC_MSI_IRQ 910 dev->msi.domain = d; 911 #endif 912 } 913 914 static inline void *dev_get_drvdata(const struct device *dev) 915 { 916 return dev->driver_data; 917 } 918 919 static inline void dev_set_drvdata(struct device *dev, void *data) 920 { 921 dev->driver_data = data; 922 } 923 924 static inline struct pm_subsys_data *dev_to_psd(struct device *dev) 925 { 926 return dev ? dev->power.subsys_data : NULL; 927 } 928 929 static inline unsigned int dev_get_uevent_suppress(const struct device *dev) 930 { 931 return dev->kobj.uevent_suppress; 932 } 933 934 static inline void dev_set_uevent_suppress(struct device *dev, int val) 935 { 936 dev->kobj.uevent_suppress = val; 937 } 938 939 static inline int device_is_registered(struct device *dev) 940 { 941 return dev->kobj.state_in_sysfs; 942 } 943 944 static inline void device_enable_async_suspend(struct device *dev) 945 { 946 if (!dev->power.is_prepared) 947 dev->power.async_suspend = true; 948 } 949 950 static inline void device_disable_async_suspend(struct device *dev) 951 { 952 if (!dev->power.is_prepared) 953 dev->power.async_suspend = false; 954 } 955 956 static inline bool device_async_suspend_enabled(struct device *dev) 957 { 958 return !!dev->power.async_suspend; 959 } 960 961 static inline bool device_pm_not_required(struct device *dev) 962 { 963 return dev->power.no_pm; 964 } 965 966 static inline void device_set_pm_not_required(struct device *dev) 967 { 968 dev->power.no_pm = true; 969 } 970 971 static inline void dev_pm_syscore_device(struct device *dev, bool val) 972 { 973 #ifdef CONFIG_PM_SLEEP 974 dev->power.syscore = val; 975 #endif 976 } 977 978 static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags) 979 { 980 dev->power.driver_flags = flags; 981 } 982 983 static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags) 984 { 985 return !!(dev->power.driver_flags & flags); 986 } 987 988 static inline void device_lock(struct device *dev) 989 { 990 mutex_lock(&dev->mutex); 991 } 992 993 static inline int device_lock_interruptible(struct device *dev) 994 { 995 return mutex_lock_interruptible(&dev->mutex); 996 } 997 998 static inline int device_trylock(struct device *dev) 999 { 1000 return mutex_trylock(&dev->mutex); 1001 } 1002 1003 static inline void device_unlock(struct device *dev) 1004 { 1005 mutex_unlock(&dev->mutex); 1006 } 1007 1008 DEFINE_GUARD(device, struct device *, device_lock(_T), device_unlock(_T)) 1009 1010 static inline void device_lock_assert(struct device *dev) 1011 { 1012 lockdep_assert_held(&dev->mutex); 1013 } 1014 1015 static inline struct device_node *dev_of_node(struct device *dev) 1016 { 1017 if (!IS_ENABLED(CONFIG_OF) || !dev) 1018 return NULL; 1019 return dev->of_node; 1020 } 1021 1022 static inline bool dev_has_sync_state(struct device *dev) 1023 { 1024 if (!dev) 1025 return false; 1026 if (dev->driver && dev->driver->sync_state) 1027 return true; 1028 if (dev->bus && dev->bus->sync_state) 1029 return true; 1030 return false; 1031 } 1032 1033 static inline void dev_set_removable(struct device *dev, 1034 enum device_removable removable) 1035 { 1036 dev->removable = removable; 1037 } 1038 1039 static inline bool dev_is_removable(struct device *dev) 1040 { 1041 return dev->removable == DEVICE_REMOVABLE; 1042 } 1043 1044 static inline bool dev_removable_is_valid(struct device *dev) 1045 { 1046 return dev->removable != DEVICE_REMOVABLE_NOT_SUPPORTED; 1047 } 1048 1049 /* 1050 * High level routines for use by the bus drivers 1051 */ 1052 int __must_check device_register(struct device *dev); 1053 void device_unregister(struct device *dev); 1054 void device_initialize(struct device *dev); 1055 int __must_check device_add(struct device *dev); 1056 void device_del(struct device *dev); 1057 1058 DEFINE_FREE(device_del, struct device *, if (_T) device_del(_T)) 1059 1060 int device_for_each_child(struct device *dev, void *data, 1061 int (*fn)(struct device *dev, void *data)); 1062 int device_for_each_child_reverse(struct device *dev, void *data, 1063 int (*fn)(struct device *dev, void *data)); 1064 struct device *device_find_child(struct device *dev, void *data, 1065 int (*match)(struct device *dev, void *data)); 1066 struct device *device_find_child_by_name(struct device *parent, 1067 const char *name); 1068 struct device *device_find_any_child(struct device *parent); 1069 1070 int device_rename(struct device *dev, const char *new_name); 1071 int device_move(struct device *dev, struct device *new_parent, 1072 enum dpm_order dpm_order); 1073 int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid); 1074 1075 static inline bool device_supports_offline(struct device *dev) 1076 { 1077 return dev->bus && dev->bus->offline && dev->bus->online; 1078 } 1079 1080 #define __device_lock_set_class(dev, name, key) \ 1081 do { \ 1082 struct device *__d2 __maybe_unused = dev; \ 1083 lock_set_class(&__d2->mutex.dep_map, name, key, 0, _THIS_IP_); \ 1084 } while (0) 1085 1086 /** 1087 * device_lock_set_class - Specify a temporary lock class while a device 1088 * is attached to a driver 1089 * @dev: device to modify 1090 * @key: lock class key data 1091 * 1092 * This must be called with the device_lock() already held, for example 1093 * from driver ->probe(). Take care to only override the default 1094 * lockdep_no_validate class. 1095 */ 1096 #ifdef CONFIG_LOCKDEP 1097 #define device_lock_set_class(dev, key) \ 1098 do { \ 1099 struct device *__d = dev; \ 1100 dev_WARN_ONCE(__d, !lockdep_match_class(&__d->mutex, \ 1101 &__lockdep_no_validate__), \ 1102 "overriding existing custom lock class\n"); \ 1103 __device_lock_set_class(__d, #key, key); \ 1104 } while (0) 1105 #else 1106 #define device_lock_set_class(dev, key) __device_lock_set_class(dev, #key, key) 1107 #endif 1108 1109 /** 1110 * device_lock_reset_class - Return a device to the default lockdep novalidate state 1111 * @dev: device to modify 1112 * 1113 * This must be called with the device_lock() already held, for example 1114 * from driver ->remove(). 1115 */ 1116 #define device_lock_reset_class(dev) \ 1117 do { \ 1118 struct device *__d __maybe_unused = dev; \ 1119 lock_set_novalidate_class(&__d->mutex.dep_map, "&dev->mutex", \ 1120 _THIS_IP_); \ 1121 } while (0) 1122 1123 void lock_device_hotplug(void); 1124 void unlock_device_hotplug(void); 1125 int lock_device_hotplug_sysfs(void); 1126 int device_offline(struct device *dev); 1127 int device_online(struct device *dev); 1128 void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode); 1129 void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode); 1130 void device_set_of_node_from_dev(struct device *dev, const struct device *dev2); 1131 void device_set_node(struct device *dev, struct fwnode_handle *fwnode); 1132 1133 static inline int dev_num_vf(struct device *dev) 1134 { 1135 if (dev->bus && dev->bus->num_vf) 1136 return dev->bus->num_vf(dev); 1137 return 0; 1138 } 1139 1140 /* 1141 * Root device objects for grouping under /sys/devices 1142 */ 1143 struct device *__root_device_register(const char *name, struct module *owner); 1144 1145 /* This is a macro to avoid include problems with THIS_MODULE */ 1146 #define root_device_register(name) \ 1147 __root_device_register(name, THIS_MODULE) 1148 1149 void root_device_unregister(struct device *root); 1150 1151 static inline void *dev_get_platdata(const struct device *dev) 1152 { 1153 return dev->platform_data; 1154 } 1155 1156 /* 1157 * Manual binding of a device to driver. See drivers/base/bus.c 1158 * for information on use. 1159 */ 1160 int __must_check device_driver_attach(struct device_driver *drv, 1161 struct device *dev); 1162 int __must_check device_bind_driver(struct device *dev); 1163 void device_release_driver(struct device *dev); 1164 int __must_check device_attach(struct device *dev); 1165 int __must_check driver_attach(struct device_driver *drv); 1166 void device_initial_probe(struct device *dev); 1167 int __must_check device_reprobe(struct device *dev); 1168 1169 bool device_is_bound(struct device *dev); 1170 1171 /* 1172 * Easy functions for dynamically creating devices on the fly 1173 */ 1174 __printf(5, 6) struct device * 1175 device_create(const struct class *cls, struct device *parent, dev_t devt, 1176 void *drvdata, const char *fmt, ...); 1177 __printf(6, 7) struct device * 1178 device_create_with_groups(const struct class *cls, struct device *parent, dev_t devt, 1179 void *drvdata, const struct attribute_group **groups, 1180 const char *fmt, ...); 1181 void device_destroy(const struct class *cls, dev_t devt); 1182 1183 int __must_check device_add_groups(struct device *dev, 1184 const struct attribute_group **groups); 1185 void device_remove_groups(struct device *dev, 1186 const struct attribute_group **groups); 1187 1188 static inline int __must_check device_add_group(struct device *dev, 1189 const struct attribute_group *grp) 1190 { 1191 const struct attribute_group *groups[] = { grp, NULL }; 1192 1193 return device_add_groups(dev, groups); 1194 } 1195 1196 static inline void device_remove_group(struct device *dev, 1197 const struct attribute_group *grp) 1198 { 1199 const struct attribute_group *groups[] = { grp, NULL }; 1200 1201 return device_remove_groups(dev, groups); 1202 } 1203 1204 int __must_check devm_device_add_groups(struct device *dev, 1205 const struct attribute_group **groups); 1206 int __must_check devm_device_add_group(struct device *dev, 1207 const struct attribute_group *grp); 1208 1209 /* 1210 * Platform "fixup" functions - allow the platform to have their say 1211 * about devices and actions that the general device layer doesn't 1212 * know about. 1213 */ 1214 /* Notify platform of device discovery */ 1215 extern int (*platform_notify)(struct device *dev); 1216 1217 extern int (*platform_notify_remove)(struct device *dev); 1218 1219 1220 /* 1221 * get_device - atomically increment the reference count for the device. 1222 * 1223 */ 1224 struct device *get_device(struct device *dev); 1225 void put_device(struct device *dev); 1226 1227 DEFINE_FREE(put_device, struct device *, if (_T) put_device(_T)) 1228 1229 bool kill_device(struct device *dev); 1230 1231 #ifdef CONFIG_DEVTMPFS 1232 int devtmpfs_mount(void); 1233 #else 1234 static inline int devtmpfs_mount(void) { return 0; } 1235 #endif 1236 1237 /* drivers/base/power/shutdown.c */ 1238 void device_shutdown(void); 1239 1240 /* debugging and troubleshooting/diagnostic helpers. */ 1241 const char *dev_driver_string(const struct device *dev); 1242 1243 /* Device links interface. */ 1244 struct device_link *device_link_add(struct device *consumer, 1245 struct device *supplier, u32 flags); 1246 void device_link_del(struct device_link *link); 1247 void device_link_remove(void *consumer, struct device *supplier); 1248 void device_links_supplier_sync_state_pause(void); 1249 void device_links_supplier_sync_state_resume(void); 1250 void device_link_wait_removal(void); 1251 1252 /* Create alias, so I can be autoloaded. */ 1253 #define MODULE_ALIAS_CHARDEV(major,minor) \ 1254 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor)) 1255 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \ 1256 MODULE_ALIAS("char-major-" __stringify(major) "-*") 1257 1258 #endif /* _DEVICE_H_ */ 1259